luense



F. H. LUENSE.

AEHOPLANE.

APPLICATION men MAY 24. 1915.

Patented'Nov. 4,1919. 3 is Z 9 32 3SHEETSS HEETI.

W/T/VESSES. INVEN TOR 04 am a -4 rromvsy F. H. LUENSE.

'AEBOPLANE.

APPLICATION FILED MAY 24". 1915.

Patented N 0v. 4, 1919.

3 SHEETS-SHEET 2 WITNESSES:

F. H. 'LUENSE.

AEROPLANE. APPLICATION FILED MAY 2%1915. 1,320,772. Patented Nov. 4, 1919.

3 SHEETSSHEET 3- 3 a 41 33 a? 2 7 Z: 4% y a? 1% e, 37 a 39 7' 1 3g 4 o 12 1 20 12 aa 5 WITNESSES: Ill/MENTOR A 7TOR/VEY nrc.

FREDERICK H. LUENSE, OF NEW YORK, N. Y.

AEROIPLAN'E.

Application filed May 24, 1915.

To all whom it may concern:

Belt known that I, FREDERICK H. LUENsE a sub ect of the Emperor of Germany, and a resident of the city of New York, in the This invention relates to the aeroplanetype of flying machines, and to the various classes thereof, such as monoplanes, biplanes, and multiplanes.

The principal object of my invention is to provide an aeroplane having means inherent thereto that will automatically maintain the machine in proper lateral and longitudinal equilibrium and impart thereto complete in herent stability.

Other objects and advantages will hereinafter appear.

Several definitions of terms and principles incorporated below will aid in explaining and in a clearer understanding of the detailed description which is to follow.

By the term aerofoil is here meant a sustaining surface of an aeroplane having the required transverse-sectional shape, and by this term these planes will be hereinafter referred to.

According to the invention it is contemplated to utilize a floating aerofoil, by which is meant an aerofoil hinged at or near its leading edge in such manner that when the machine is in motion the aerofoil will be freely swung by the pressure of the air to a position which is near and angular to the line of direction of flight of the machine and is termed the angle of incidence of the aerofoil.

The force whichis created by the speed of the aerofoil through the air and which is trying to maintain it in horizontal position as well as to sustain the entire machineis here termed the support, and the point of concentration of said force upon the aerofoil is called the center of support.

The greater the speed of the machine the lesser becomes the angle of incidence, and vice versa, and, in the form of aerofoil here selected, the greater said speed and the lesser the angle of incidence the farther does the center of support travel toward the rear edge.

By speed is here meant motion of the aerofoil relatively to the air through which Specification of Letters Patent.

Patented Nov. 4, 1919.

Serial No. 29,988.

the machine travels, and has no relation to speed relatively to the ground.

By the directive body is meant the general body of the machine which carries the propelling, steering, and other operating mechanism, and in the direction of the longitudinal aXis of which the entire machine tends to travel.

In the accompanying drawings,

Figure 1 is a general plan view of the aeroplane of the monoplane type.

Fig. 2- is a side elevation of the aeroplane shown in Fig. 1.

i Fig. 3 and Fig. 4 are elevations of the mechanism that coacts with the aerofoils to restore the lateral equilibrium of the aeroplane.

Fig. 5 is an enlarged side elevation of the aeroplane, similar to the view in Fig 2, but showing the various parts of the operating mechanism of the machine.

Fig. 6 is a front elevation of the aeroplane.

Fig.7 is a side elevation of a biplane type of aeroplane embodying the invention.

Fig. 8 is a front elevation f the aeroplane shown in Fig. 7.

A directive body 1, shown in outline, is

constructed of frame-work of suitable material, and is provided with a propeller 2 at the front end thereof, a horizontal rudder 3 and a vertical rudder 4 at the rear thereof, a landing gear 5, and a rear landing spur 6. To the body 1 is secured a beam 7- of steel tubing which passes therethrough and extends perpendicularly to the body at each side thereof. Said beam is located relatively to the body 1 at a point which is the center of gravity of the body as considered together with the aforementioned parts that are connected thereto. At each side of the body 1 is located an aerofoil 8 which has its leading edge 9 hinged or pivoted upon the beam 7, whereby each of the aerofoils is adaptable to swing transversely about said beam, independently of each other and upwardly and downwardly with relation to the body 1, as it is viewed in the drawing. Stopping projections 10 secured to the sides of the body 1 serve to limit the upward swinging of the aerofoils to a position which is about 3 degrees above a horizontal plane with relation to the body 1, as it is viewed in the drawing, or 3 degrees above the line of direction of flight, and stopping projections 11 serve to limit the downward swinging of the aerofoils to a position which is 20 degrees below the line of direction of flight. The beam 7 is rigidly secured to the body 1, and the aerofoils 8 are firmly secured in proper position at the leading edges 9 by means of stays 12 and by their fitting around the beam 7 whereby any movement of the aerofoils relatively to the body 1, other than swinging about said beam and leading edges, is prevented.

Within the directive body 1 and below the aerofoils 8 is located a frame 13 which is hinged at it end l t to the beam 7 and extends therefrom toward the rear of said body approximately parallel to the aerofoils. Upon the frame 13 and adjacent to the beam 7 is secured the propeller-driving motor 15, and at the opposite end 16 of said frame is provided the operators seat 17. Between the motor 15 and the seat 17 is pivotally mounted a wheel or pulley-segment 18 upon a hanger 19 secured to the underside of frame 13. Steel cables 20 pass around a groove 21 in pulley 18 and have their ends 22 secured at points 23 to the aerofoils 8, whereby the frame 13 with the motor 15 and seat 17 are sustained by and held to the aerofoils 8 in the position shown and may be swung upwardly and clownwardly together with the aerofoils around their common pivot about beam 7. Should one of the aerofoils 8 be raised independently the other aerofoil would be swung in an opposite direction and descend downwardly, Fig. 3, and should one of the aerofoils be caused to descend during flight the other aerofoil would be lifted by the pressure thereunder. The rim 18 of pulley 18 is disposed in 12L plane which is approximately perpendicular to the aerofoils 8, in which plane lie the center of gravity of the entire machine and also the centers of support of the aerofoils 8 when they are disposed at about 15 degrees to the line of direction of travel of the machine, thi being the angle of incidence which is designed to be maintained by the aerofoils when the Ina-- chine travels at its lowest designed speed. The axis about which the aerofoils 8 swing must be in front of the center of gravity of the machine, and in construction of the aerofoils 8 they are given such a crosssectional configuration that the center of support of the aerofoils will move toward their rear edges as the angle of incidence becomes less than their maximum flying angle of 15 degrees.

The motor-shaft 24: carries a bevel gear 25 that meshes with a pair of idle gears 26 rotatably mounted upon beam 7 which in turn mesh with a bevel gear 27 secured upon the drive shaft 28 of propeller 2, by which means the propeller 2 is effectively driven by the motor 15 at whatever angle of inclination thereto it may assume together with the frame 13 and aerofoils 8 during flight.

To the front of the directive body and immediately to the rear of propeller 2 is secured a tubular cross-beam 29 which carries an auxiliary compensating aerofoil 31 at each side of the body 1, and directly opposite and in front of each of the sustaining aerofoils 8. The aerofoils 31 have their leading edges 32 pivoted to the beam 29 and are adapted to freely swing transversely therearound. Each of the sustaining aerofoils 8 carries a lever 33 which is adaptable to bear upon and engage with a lever 34 secured to the auxiliary aerofoil 31 directly opposite thereto. hile the machine travels at its lowest designed speed the aerofoils 31 carry no load whatever and assume any position in a direction of least resistance. When the sustaining aerofoils 8 are swung to a smaller angle of incidence than about 15 degrees to the line of direction of flight the levers 33 thereof bear against the levers 3d and thereby cause the auxiliary aerofoils 31 to become disposed at an effective angle of incidence with respect to the direction of flight, Fig. 5, whereby they attain an effective lifting capacity toward the machine at the front end of the body 1, the object of which will be hereinafter seen.

In the operation of the machine during flight, the operator i seated in seat 17 and at this place attends to the propeller-motor 15 and manipulates the wheel 35 that controls, by means of cables 36, the action of the horizontal and vertical rudders 3, 4. Should a gust of wind strike one of the sustaining aerofoils 8 and create an undue pressure thereunder, soas to thereby disturb the lateral equilibrium of the machine and threaten to overthrow it about the axis of the directive body 1, the aerofoil would be caused to swing about its hinge at leading edge 9 upwardly or toward the line of direction of flight and by means of cables 20 and wheel 18 would actuate the otner aerofoil 8 to swing transversely in an opposite direction, Fig. 3. This would increase the angle of incidence of aerofoil 8 and consequently alsothe pressure thereunder, which pressure would counterbalance the undue pressure created under the aerofoil 8 by said ust of wind and prevent any undue distur ance of the lateral equilibrium of the machine. With the machine thus, maintained in lateral equilibrium and the effect of such peculiar gust of wind ceasing the aerofoils 8, 8 would at once adjust and restore themselves automatically to normal alinement in the same plane, Fig; 4:. Should any peculiar eddy of air create low pressure under one of the aerofoils 8 and cause it to descend, so as to tend to disturb the lateral balance of the machine, the other aerofoil would be thereby swung oppositely and caused to rise, and the pressure under the latter aerofoil being consequently decreased it would counterbalance the low pressure created under the former aerofoil and thereby maintain the machine in lateral equilibrium.

The longitudinal equilibrium of the machine is maintained by the action of the sustaining aerofoils 8 upon the compensating aerofoils 31, as willbe hereinafter seen. As the machine proceeds along its course, the aerofoils 8, being free to float or swing transversely about their leading edges are thereby caused to consequently adjust themselves automatically to various angles of incidence corresponding to varying speeds of the machine. When the aeroplane flies at its,

lowest designed speed, the aerofoils are dis- .iosed at an angle of incidence of about 15 degrees below the line of direction of'flight, and at this angle of incidence the center of support of the aerofoils is located at about the line 8 which is coincident with the center of gravity of the entire machine, and hence the aeroplane is properly balanced longitudinally. WVith increase of speed of.

the machine the angle of incidence decreases and the center of support consequently shifts from the center of gravity point 8, moving away therefrom toward the rear edge of the aerofoil. It follows, therefore, that at such decreased angles of incidence, the center of gravity of the machine being in front of its center ofsupport, the front of said aerofoils might be caused to descend or dive on account of the lack of support thereat. And in order to prevent such tendency of the aerofoils to dive additional means of supportis provided in front of the center of gravity through the medium of the compensating aerofoils 31, which are automatically operated to su ply the proper support as it is required. is has been described above, the sustaining aerofoils 8 cause the levers 33 to actuate the levers 34 and dispose the compensating aerofoils 31 to such an angle of incidence that they at tain an effective lifting capacity sufflcient to supply the deficiency of lifting power at the front of the aerofoils 8 and in this manner maintain the machine in proper longitudi nal equilibrium when required under the said conditions. i

The modification of the machine in Figs. 7, 8 shows an adaptation of the invention to the biplane type of aeroplane. According to this machine, the directive body, rudder, the lower aerofoils 8, the driving and controlling mechanism, etc., are all similar to the monoplane shown in Figs. 1, 2, 5, 6, and the description in connection with the monoplane will therefore suflice for the biplane.

The front struts 37 of the biplane are hinged to the aerofoils 8 and are supported firmly in upright position by means of stays 7 and by bracing wires 39. To the struts 37 are pivotally connected upper aerofoils 40, and at the rear of the aerofoils 8, 40 are located rear struts 41 that are held to each other by means of bracing wires 42 and are pivoted at their extremities 4:3 to the upper and lowe aerofoils 40, 8. The upper aerofoils 40 are held together at their front edges by a sleeve 44 in such a manner as to permit the aerofoils to swing either simultaneously together or independently of each other. As the angle of incidence of aerofoils 8 fluctuates during flight, therefore, the upper aerofoils a0 are swung therewith and are at all times maintained parallel thereto, and in this manner the biplane operates similarly to the above described monoplane type )f machine embodying the invention.

It will be evident that the ability of the aerofoils 8 to adjust themselves automatically to various angles of incidence depending upon the varying speeds of the machine, whereby at any given speed the aerofoils 8 assume a definite angle of incidence, enables the machine to fly at a large variation of speed. And as a result thereof landing upon or rising fron'i the ground may be accomplished with the machine at much lower speeds than was heretoforepossible.

Variations may be resorted to within the scope of the invention, and portions of the improvements may be used without others.

Having thus described my invention, I claim 1. In a flying machine of the aeroplane type, the combination with a directive body, a propeller carried by said body, a driveshaft therefor, anda motor, of a sustaining aerofoil at each side of said body pivoted to swing in a direction transversely to its entering edge, a frame carrying said motor and for carrying the operator being su tained by said aerofoils and pivoted to swing together with the aerofoils, and gearing connecting said motor with said drive shaft.

2. In a flying machine of the aeroplane type, the combination with a directive body, a propeller carried by said body, a driveshaft therefor, and a motor, of a sustaining aerofoil at each side of said body pivoted to swing in a direction transversely to its entering edge, a frame carrying said motor sustained by said aerofoils and pivoted to swing together with the aerofoils, and means connecting said motor with said drive shaft.

3. In a flying machine of the aeroplane type, the combination with a directive body, a propeller carried by said body, a driveshaft therefor, and a motor, of a sustaining aerofoil at each side of said body pivoted to swing in a direction transversely to its entering edge, a frame carrying said motor sustained by said aerofoils and pivoted to swing together with the aerofoils at the axis about which the aerofoils swing, and means connecting said motor with said drive shaft.

4. A flying machine having a directive body, a freely floating sustaining aerofoil pivoted to swing in a direction transversely to the entering edge thereof, a propeller carried by said body, a motor therefor, a frame carrying said motor sustained by said aerofoil and pivoted to swing therewith, and means connecting said motor with said propeller.

5. A flying machine having a sustaining aerofoil pivoted to swing in a direction transversely to the entering edge thereof, a propeller carried by said body, a motor therefor, a frame carrying said motor sustained by said aerofoil and pivoted to swing therewith about the axis around which the aerofoil swings, and means connecting said motor with said propeller.

6. A flying machine having a directive body, a freely floating sustaining aerofoil pivoted on said body to swing in a direction transversely to the entering edge thereof, and a frame for carrying the operator sustained by said aerofoil and pivoted to swing therewith.

7. A flying machine having its sustaining aerofoils pivoted to swing in a direction transversely to their entering edges, a propeller, a motor therefor, a frame carrying said motor sustained by said aerofoils and pivoted to swing therewith, means connecting said aerofoils to each other and to said frame to cause them to swing together with other and to said frame to cause them to swing together with the frame and to simultaneously enable one of the aerofoils to swing in a direction opposite to the direcion in which the other aerofoil is swinging relatively thereto.

9. A flying machine having sustaining aerofoils pivoted to swing in a direction transversely to their entering edges, a frame for carrying the operator sustained by said aerofoils and pivoted to swing therewith about the axi around which the aerofoils swing, and means connecting said aerofoils to each other and to said frame to cause them to swing together with the frame and to simultaneously enable one of the aerofoils to swing in a direction opposite to the direction in which the other aerofoil is swinging relatively thereto.

Signed at the city of New York, in the county of New York, and State of New York, this 22nd day of May, A. D. 1915.

FREDERICK H. LUENSE. l/Vitnes'ses CHAS. W. LARUE, B. ROMAN.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. O. 

